The researchers tracked added sugar intakes and patterns of body weight over a 27-year period in adults between the ages of 25 and 74. Over the nearly three decades added sugar consumption increased for both men and women in all age groups. Among women it jumped from about 10 percent of total calories in the early 1980s to over 13 percent by 2009. And those increases in sugar corresponded to an increase in BMI or body mass index.

The average added sugar intake in the US is now up to a whopping 22 tsp a day — an amount that snowballs into 14 five pound bags a year! Most of it, over a third, comes from sweetened drinks (soda, sweet tea, lemonade, fruit punch, etc.) and just under a third comes from candy and goodies like cookies, cake and pie. But some of it sneaks into foods you might not suspect, such as:

•When you put ketchup on your turkey burger you probably don’t think of it as added sugar, but each tbsp packs about 1 tsp of sugar (2 cubes worth).

•The second ingredient in canned tomato soup is high fructose corn syrup — the whole can packs the equivalent of 7.5 tsp (15 cubes worth) of sugar.

•And I think everyone is aware that baked goods contain sugar, but do you realize just how much? Today’s average sized muffin packs 10 tsp (20 cubes worth).

The American Heart Association recommends that women limit added sugars to about 100 calories a day and men cap it at 150 calories a day — that’s equals 6 level tsp of granulated sugar for women and 9 for men (note: just one 12 oz can of soda is the equivalent of 8 tsp of sugar).

Scoping out how much is in a packaged food can be a little tricky, because when you look at the grams of sugar per serving on nutrition labels that number does not distinguish between naturally occurring sugar and added sugar.

The only sure way to tell is to read the ingredient list. If you see the word sugar, brown sugar, corn syrup, glucose, sucrose and other –oses, corn sweeteners, high fructose corn syrup and malt, sugar has been added to the food.

On the other hand if you see grams of sugar but the only ingredients are whole foods, like pineapple chunks in pineapple juice or plain yogurt, you know that all of the sugar is naturally occurring (from Mother Nature) and currently none of the guidelines call for avoiding these foods.

Bottom line: Eating more fresh and fewer processed foods is the easiest way to avoid the sugary stuff — and the corresponding weight gain. So instead of starting your day with a blueberry muffin go for a bowl of quick cooking oats topped with fresh blueberries — they're in season now!

Cynthia Sass is a registered dietitian with master's degrees in both nutrition science and public health. Frequently seen on national TV she's a SHAPE contributing editor and nutrition consultant to the New York Rangers and Tampa Bay Rays. Her latest New York Times best seller is Cinch! Conquer Cravings, Drop Pounds and Lose Inches.